子函数改全局变量前要先声明（一般不这样用）

school = "Oldboy edu."
def change_name(name):
    global school      #改全局变量前要先声明
    print('before change',name,school)
    school = "YunNan University"
    name = "Lian"
    print('after change',name,school)
name = 'lian'
change_name(name)
print(name,school)

before change lian Oldboy edu.
after change Lian YunNan University
lian YunNan University

 

def change_name2():
    global name2
    name2='Meng'
change_name2()
print(name2)


Meng